Means for preventing loss of cold air from refrigerated spaces



July 3, 1951 H. H. voELKER MEANS FOR PREVENTING Loss oF COLD AIR FROM REFRIGERATED sPAcEs Filed Aug. 9, 1949 Jl IR N Q u.

1N VEN TOR.

HENRY H. VOELKER ATTORNEY.

Patented July 3, 1951 MEANS FOR PREVENTING LOSS OF COLD AIR FROM REFRIGERATED SPACES Henry H. Voelker, Cleveland, Ohio, assignor to l Automatic Screw Products Company, Cleveland, Ohio, a partnership I Application August 9, 1949, Serial No. 109,290

(Cl. (i2-89) 9 Claims.

This invention relates, as indicated, to methods of and means for preventing loss of cold air from a refrigerated space.

When opening the door of a refrigerator, the cold air, due to its relatively high specific gravity will fall or drop out of the refrigerator in a manner similar to that in which water would flow out of the refrigerator if the refrigerator were filled with water and the door were opened.

This cold air is replaced by lighter warm air which flows in through the open door, and which must be cooled in order to reestablish the desired temperature in the refrigerator. In order to cool this warm air which has replaced the lost cold air, the compressor unit of the refrigerator is required to operate at frequent intervals, the length of which depends, of course, on the frequency with which the refrigerator door is opened. Expressed in another way, the more frequently the door is opened, the more frequently the refrigerator compressor unit is actuated.

I have discovered, as the result of considerable experimentation a novel, unique and eicient method of preventing loss of cold air from a refrigerated space when the space is opened, as for example, when a refrigerator door is opened.

The method may be illustrated by reference to the accompanying drawings, in which Fig. 1 is a front elevational view of a refrigerator cabinet embodying my invention.

Fig. 2 is a longitudinal cross-sectional view taken on line 2 2 of Fig. 1.

Fig. 3 is a View similar to Fig. 2 but with the door in open position.

Fig. 4 is an enlarged cross-sectional view of one of the details shown in Fig. 3.

Fig. 5 is a view of the cove taken as indicated by line 5 5 of Fig. 4.

Referring more particularly to the drawings, there is illustrated a conventional household refrigerator having a refrigerated compartment or space A, which is defined by a rear wall I, side walls 2 and 3, a bottom 4 andV a top 5. The rectangular opening at the front of the space A is normally closed by means of a door 6, which is hingedly secured to the refrigerator and is provided with the usual rubber seal or tubing I which bears against the front edges or surfaces of the walls 2 and 3, bottom 4 and top 5 to effectively seal the space against loss of cold air, when the door is closed.

In accordance with the illustrated or exemplary form of the invention, I preferably stamp the metal constituting the front edge 8 of the bottom 4 in such a manner as to provide a line or series of louvers substantially parallel with the lower edge of the door 6, when the latter is in closed position. The louvers 9 extend forwardly from the edge or face 8, and in such a manner that air blown into the lower edges of these louvers will blow upwardly out of the louvers and in a plane substantially parallel with the rear wall I of the refrigerator. It will also be noted that the outlet openings or upper edges of the louvers are disposed below the rubber seal 1. when the door is in closed position. The

`reason for this will be presently explained.

Disposed Within the bottom 4, rearwardly of the face 8 of the bottom is a duct or conduit I0, preferably in the formof a cone, closed at its apex Il, and having a throat I2 extending tangentially therefrom along its entire length, the upper or open edge of this throat being in registry with the inlet or lower edges of the louvers 9.

Air is supplied to the duct or conduit I0 by means of a'slnall blower I3, preferably of the Sirocco or centrifugal type, located within a compartment of the refrigerator externally of the space A, and operated by a small motor, of say 50 watty rating, for supplying air at low velocity. Aii from the blower I3 is supplied to the base of the cone conduit I0 by means of an elbow duct I4.

Reference numeral I5 designates a conventional push button switch which automatically causes the light bulb within the refrigerator to become energized each time that the door 6 is opened. This button, as illustrated may-also be placed in circuit with the motor of the blower I3, so as to cause the blower to operate each time that the door 6 is opened, and remain in operation until the door is closed.

When the door 6 is opened, the blower I3 is energized, causing air to be blown into the duct I0, the air passing through the throat l2 of the duct and into the louvers 9, emerging from these louvers as a substantially vertical wall or curtain of air which extends across the entire width of the opening of the space A. This wall or curtain of air need not be cold air, but may be air of ordinary atmospheric temperature. This wall or curtain of air acts or serves as a barrier to prevent the cold air within the refrigerated space A from falling out through the opening at the front or entrance to the space A. This barrier is maintained as long as the door is open, and when the door is closed, the operation of the blower is automatically stopped.

It has been determined that by the use of the aforesaid Iwall, or curtain of air, the loss of cold air. when the door is opened, is reduced sufliciently so that the time intervals between operation of the refrigerator compressor or other refrigeration-producing unit, are increased at least 20%, thereby resulting in a saving of electrical energy consumed in the operation of the refrigerator.

By utilizing a tapered or conical tube as the duct I0. the air pressure is equalized along the entire tube, resulting in an equal volume of emerging air at all points throughout the length of the tube. This produces a curtain or wall vof air of uniform thickness and height.

It is desirable, also, that the air forming the wall or curtain be filtered, and for this purpose, an ordinary spun glass lter or similar air ltering device may be incorporated in the blower I3, or placed across the entrance to the duct I0.

By having the outlet edges of the louvers I disposed below the rubber seal 1, leakage of cold air from the space A downwardly into the louvers when the door 6 is in closed position is precluded.

Although the invention has been described in connection with the conventional type of household refrigerator, it will be readily understood that the invention is not limited in this respect, but is readily adapted for commercial type of refrigerators, for meat lockers, frozen food lockers, refrigerator trucks, coolers, etc.

Moreover, the curtain or barrier of air, while preferably being one formed by blowing air upwardly across the opening or entrance to the refrigerated space, may be produced in other ways, as for example, by blowing curtains or walls of air laterally across said space, as from opposite side walls of the space toward each other. The wall or curtain or air need not extend the full height of the opening, but will be effective if it extends only across the lower portion of the opening, since the cold air, which is normally lost, drops out of the lower portion of the opening.

It is to be understood that various changes in the steps and other details in the method and in the means for carrying out said method may be resorted to without departing from the scope of the subjoined claims.

Having thus described my invention, I claim:

l. In a refrigerator having a refrigerated space and---an entrance for said space, a closure for said entrance, said closure having sealing means associated therewith, said sealing means adapted to engage the walls deflning said entrance, a blower, air slots disposed in the portion of said walls deiining the lower edge of said entrance, a conduit communicating said blower with said air slots, and means for automatically actuating said 4 blower when said closure is opened, whereby a wall or curtain of air is blown upwardly across said entrance to prevent loss of cold air from said space.

2. A refrigerator, as dei'lned in claim 1, in which said air slots are dened by louvers. l

3. A refrigerator, as defined in claim 1, in which said conduit is of conical shape.

4. A refrigerator, as dened in claim 3. in which said conduit has a throat extending tangentially therefrom, said throat being in registry with said air slots.

5. In a refrigerator having a refrigerated space and an entrance to said space, means for preventing loss of cold air from said space, said means comprising a wall or curtain of air blowing upwardly across said entrance, and means for supplying said curtain of air, said last-named means including a conduit of conical shape.

6. A refrigerator, asdened in claim 5, in which said conduit has a throat extending tangentially therefrom.

7. In a refrigerator having a refrigerated space and an entrance to said space, a closure for said entrance, and means for preventing loss of cold air from said space while said closure is opened, said means comprising means for blowing air upwardly across said entrance, and including a blower, and a conduit of conical shape.

8. A refrigerator, as defined in claim 7, in which said conduit has a throat extending tangentially therefrom.

9. In a refrigerator having a refrigerated space and walls defining 'an entrance for said space, a closure for said entrance, a blower, air slots disposed in the portion of said walls defining the lower edge of said entrance, a conduit communicating said blower with said air slots, and means for automatically actuating said blower when said closure is opened, whereby a wall or curtain oi air is blown upwardly across said entrance to prevent loss of cold air from said space.

HENRY H. VOELKER.

' REFERENCES crrED The following references are of record in the file of this patent:

UNITED STATES PATENTS Numberl Name Date 907,609 Kirk Dec. 22, 1908 935,850 Kirk Oct. 5, 1909 1,649,290v De Neen Nov. 15, 1927 2,241,854 Hall May 13, 1941 2,462,705 Abeling Feb. 22, 1949 2,494,480 MacMaster Jan. 10, 1950 2,500,606 Dosmar Mar. 14, 1950 

